Bellringer 2/12
List 3 foods that are sources of protein
Objective
 I will learn about the function, sources, and
recommended intake of protein
What is Protein?
 Remove the water & about 75% of body weight is
protein.
 Muscle, bone, skin, hair, and virtually every other
body part or tissue. (25% of muscle)
 At least 10,000 different proteins make the body
what it is.
Protein
• Building blocks of the human body
•
Known as Amino Acids
• An energy yielding nutrient
composed of carbon, hydrogen,
oxygen, and nitrogen.
Amino Acids
 There are 20 different
ones, but 9 are
essential for good
health.
 Essential (9) and
Nonessential (11)
Protein Functions in the Body
 Build and repair body tissue
 Maintain cell growth (enzymes)
 Hormones
 Fluid balance
 Acid base
 Transport
 Energy
Proteins in the Body
 Roles of Proteins

Building Materials for Growth and
Maintenance = LIFE

A matrix of collagen is filled with minerals to
provide strength to bones and teeth.

Replaces tissues including the skin, hair, nails, and
GI tract lining
Build and Repair Body Tissues
 Form structure of
muscles, organs,
skin, blood, hair,
nails, and other
body parts
 As body grows,
protein helps make
new tissues
Proteins in the Body
 Roles of Proteins
 Enzymes are proteins that facilitate
anabolic (building up) and catabolic
(breaking down) chemical reactions.
Proteins in the Body
 Roles of Proteins

Hormones regulate body processes and some
hormones are proteins.

An example is insulin.
Proteins in the Body
 Roles of Proteins
 Regulators of Fluid Balance
Plasma proteins attract water
 Maintain the volume of body fluids to prevent edema
which is excessive fluid
 Maintain the composition of body fluids

Proteins in the Body
 Roles of Proteins
 Acid-Base Regulators

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Act as buffers by keeping solutions acidic or alkaline
Acids are compounds that release hydrogen ions in a solution.
Bases are compounds that accept hydrogen ions in a solution.
Acidosis is high levels of acid in the blood and body fluids.
Alkalosis is high levels of alkalinity in the blood and body
fluids.
Proteins in the Body
 Roles of Proteins
 Transporters
Carry lipids, vitamins, minerals and oxygen in the
body
 Act as pumps in cell membranes, transferring
compounds from one side of the cell membrane to the
other

Proteins in the Body
 Roles of Proteins
 Source of energy and
glucose if needed
 Other Roles
Blood clotting by producing
fibrin which forms a solid
clot
 Vision by creating lightsensitive pigments in the
retina

Protein provides energy
 Can take the place of
some fat and
carbohydrate
 Excess protein
converted to energy
 Stored as fat
Fats and carbs cannot replace
protein
 Needed to replace wear
and tear of tissue and
keep up protein
concentration in the
blood
 Excess protein, once
converted to energy,
cannot convert back to
protein
Must be supplied daily
 Constantly needed to
replace wear and tear
of tissue and keep up
protein concentration
in the blood serum
Bellringer 2/16
 Name 2 functions of proteins
Excessive Protein
Converted back to energy
May do more harm than good
Not necessary to eat a lot
The best sources of protein
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Milk
Eggs
Fish
Poultry
Red Meat
Soy
Dietary Protein
 Complete protein contains all the essential
amino acids needed to build new proteins.

Animal sources of protein tend to be
complete
 Incomplete proteins sources lack one or
more essential amino acids that the body
can't make from scratch or create by
modifying another amino acid

These usually come from fruits,
vegetables, grains, and nuts.
Complete Protein
 Any food that has all 9
essential amino acids.
 All animal proteins are
classified as complete
proteins.
 Support growth and
maintenance of body
tissue
Incomplete Amino Acids
•
 Provide normal
maintenance
 Do not support growth
 Some plant foods contain
protein, but not all essential
amino acids
 Beans, Nuts, grains,
legumes, and peanut butter
 Legumes: peanuts, black
eyed-peas, kidney beans,
black beans, lima, lentils,
chick peas
Eat a variety of food
 Make certain the body
gets all the essential
amino acids.
 Make protein complete


Combine plant and
animal food
Combining plant
protein from variety of
cereals and grains
Incomplete Proteins
 Combine to create “Complementary”
Proteins
 Combine incomplete proteins with animal
proteins to extend animal proteins
Protein needs influenced by
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Age
Body Size
Quality of the proteins
Physical state of the
person
 3-6 ounces per day or
2-3 “servings”
Protein
 Adults need 0.8 grams of protein/kg of body
weight per day to keep from slowly
breaking down their own tissues
 Just over 7 grams of protein are needed for
every 20 pounds of body weight
RDA for Protein
 Males: 52
grams/day
 Females: 46
grams/day
You need protein for your muscles, bones, and
the rest of your body. Exactly how much you
need changes with age:

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Babies need about 10 grams a day.
School-age kids need 19-34 grams a day.
Teenage boys need up to 52 grams a day.
Teenage girls need 46 grams a day.
Adult men need about 56 grams a day.
Adult women need about 46 grams a day (71 grams, if
pregnant or breastfeeding)
 You should get at least 10% of your daily calories, but not
more than 35%, from protein, according to the Institute of
Medicine.
Calculations
How to Calculate Your Protein Needs:
1. Weight in pounds divided by 2.2 = weight in
kg
2. Weight in kg x (0.8-1.8 gm/kg) = protein
gm.
 Use a lower number if you are in good health and are
sedentary (i.e., 0.8). Use a higher number (between 1 and
1.8) if you are under stress, are pregnant, are recovering
from an illness, or if you are involved in consistent and
intense weight or endurance training.
Do athletes need more??
 Extra protein does not build muscle, once
body uses what it needs, extra protein is used
as energy or stored as fat.
 A little more is okay, but not an excess.
 Best way to gain muscle is by exercising
 Benefits of extra protein is for muscle
rebuilding
 A balanced diet can easily provide enough
protein for an athlete, and protein supplements
are not necessary.
Protein Supplements
Protein Powders:
 Whey- water soluble milk protein
 Soy
 Casein –protein that causes milk
allergies
When to add extra protein:
 Starting a workout
program to gain muscle
 Training/amping up your
workout or training
 Recovering from injury
 Changing to a vegan diet
Health Effects and Recommended Intakes
of Protein
 Protein and Amino Acid Supplements

Protein Powders have not been found
to improve athletic performance.
Purified protein preparations increase the
work of the kidneys.
 Most professionals recommend natural
proteins from diet

Here are examples of amounts
of protein in food:
 1 cup of milk has 8 grams of protein
 A 3-ounce piece of meat has about 21 grams
of protein
 1 cup of dry beans has about 16 grams of
protein
 An 8-ounce container of yogurt has about 11
grams of protein
How much protein does your favorite food provide? Follow
this chart to find out:
Food
Milk
Yogurt
Greek yogurt
Egg
Cheese
Beans
Nut butters
Ground beef, cooked
Chicken breast,
cooked
Fish, salmon, cooked
Tofu
Quinoa
Serving Size
1 cup
1 cup
1 cup
1
1 ounce
½ cup
2 tablespoons
4 ounces
Grams of Protein
8
8
12 to 15
7
7
7 to 9
5 to 8
29
4 ounces
27
4 ounces
½ cup
½ cup
29
20
4
Soy
To help you make lower-fat
protein choices
 Choose meats that are leaner cuts and trim away
any fat you can see. For chicken and turkey, remove
the skin to reduce fat.
 Substitute pinto or black beans for meat in chili and
tacos.
 Choose low-fat or fat-free milk and yogurt.
 Choose low-fat or fat-free cheese.
 Choose egg whites or pasteurized egg white
products.
Insufficient Protein
 Lower one’s resistance to
disease
 Damage liver
 Death
 Tiredness
 Weight loss
 Lack of energy
 Stunt growth
 Not common in U.S.
Insufficient Protein
 Protein-energy
Malnutrition
 Kwashiorkor
 Marasmus
Health Effects and Recommended Intakes
of Protein
Marasmus
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Infancy, 6 to 18 months of age
Severe deprivation or impaired absorption of
protein, energy, vitamins and minerals
Develops slowly
Severe weight loss and muscle wasting,
including the heart
< 60% weight-for-age
Anxiety and apathy
Good appetite is possible
Hair and skin problems
PEM
Health Effects and Recommended Intakes
of Protein
Kwashiorkor
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Older infants and young children, 18
months to 2 years of age
Inadequate protein intake, infections
Rapid onset
Some muscle wasting, some fat retention
Growth is 60-80% weight-for-age
Edema and fatty liver
Apathy, misery, irritability and sadness
Loss of appetite
Hair and skin problems
Q&A
 Which has more protein?
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1 cup of whole milk
1 cup of vegetarian baked beans
3 ounces of beef
1 large egg
3 ounces of beef
Q&A
Is it true that complementary proteins must
be eaten together to count as a complete
protein source?
NO. In the past, it was thought that these complementary
proteins needed to be eaten at the same meal for your body
to use them together. Now studies show that your body can
combine complementary proteins that are eaten within the
same day.
Q&A
 True or false: Our bodies are good at storing
protein?
FALSE. Our bodies don't store proteins the
way they store carbs and fats. That's why you
need a steady supply of protein every day.
Q&A
 True or False: You can build muscle by
eating protein right after a workout.
TRUE. Protein can help repair muscles after
working out. Many studies show that having
high-protein foods or drinks soon after exercise
helps build and restore muscle. But protein is
only part of the story. The key nutrient to
strengthen muscles is carbohydrates